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Chinese Optics Letters 2020年第7期18卷 56-59页

作者： zhongkai zhang Zunren Lü Xiaoguang Yang Hongyu Chai Lei Meng Tao Yang Key Laboratory of Semiconductor Materials Science Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

We report 25 Gb/s high-speed directly modulated ground-state operation of 1.3 μm In As/Ga As quantum dot(QD) lasers grown by molecular beam epitaxy. The active region of the lasers consists of eight layers of p-doped In As QDs with high uniformity and density. Ridge-waveguide lasers with a 3-μm-wide and 300-μm-long cavity show a low threshold current of 14.4 m A at 20°C and high temperature stability with a high characteristic temperature of 1208 K between 20°C and 70°C. Dynamic response measurements demonstrate that the laser has a 3 d B bandwidth of 7.7 GHz at 20°C and clearly opened eye diagrams even at high temperatures up to 75°C under a 25 Gb/s direct modulation rate.

关键词： semiconductor lasers quantum dot molecular beam epitaxy direct modulation

Current-collapse suppression and leakage-current decrease in AlGaN/GaN HEMT by sputter-TaN gate-dielectric layer

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Journal of Semiconductors 2024年第7期45卷 70-75页

作者： Bosen Liu Guohao Yu Huimin Jia Jingyuan Zhu Jiaan Zhou Yu Li Bingliang zhang zhongkai Du Bohan Guo Lu Wang Qizhi Huang Leifeng Jiang Zhongming Zeng Zhipeng Wei Baoshun zhang State Key Laboratory of High-Power Semiconductor Laser School of PhysicsChangchun University of Science and TechnologyChangchun 130022China Nanofabrication facility Suzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of SciencesSuzhou 215123China Suzhou Powerhouse Electronics Technology Co. Ltd.Suzhou 215123China

In this paper, we explore the electrical characteristics of high-electron-mobility transistors(HEMTs) using a TaN/AlGaN/GaN metal insulating semiconductor(MIS) structure. The high-resistance tantalum nitride(TaN) film prepared by magnetron sputtering as the gate dielectric layer of the device achieved an effective reduction of electronic states at the TaN/AlGaN interface, and reducing the gate leakage current of the MIS HEMT, its performance was enhanced. The HEMT exhibited a low gate leakage current of 2.15 × 10^(-7) mA/mm and a breakdown voltage of 1180 V. Furthermore, the MIS HEMT displayed exceptional operational stability during dynamic tests, with dynamic resistance remaining only 1.39 times even under 400 V stress.

关键词： AlGaN/GaN MIS HEMTs gate dielectric layer depletion-mode gate reliability I_(on)/I_(off)ratio

Preliminary performance evaluation of Beidou spaceborne atomic clocks

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Preliminary performance evaluation of Beidou spaceborne atom...

圆型限制性三体问题下Halo-绕月轨道的星间测距定轨

第五届中国卫星导航学术年会

作者： Peiyuan Zhou Lan Du zhongkai zhang Yu Lu Yueyong Lian College of Navigation and Aerospace Engineering Information Engineering University

The performance of spaceborne atomic clock is one of the key factors that impact the accuracy of satellite navigation system positioning,navigation and timing（PNT）.With the officially operation of Chinese Beidou satellite navigation system at the end of 2012,it is extremely necessary to conduct a comprehensive evaluation of the performance of the spaceborne atomic ***,this paper introduces two performance evaluation indices of spaceborne atomic clock and their calculation methods,namely the frequency stability and short‐term prediction ***,based on the measured data of Beidou satellite clock error,we make an analysis of the performance indices of the atomic clock,and the results was compared with the GPS spaceborne rubidium clocks,and thus obtained some useful conclusions,which has important significance to improve Beidou satellite navigation system.

关键词： Spaceborne atomic clock.Frequency stability.Short‐term prediction

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测绘学报 2013年第2期42卷 184-190页

作者：杜兰张中凯于亮陈世杰信息工程大学导航与空天目标工程学院中国科学院上海天文台 61363部队

在传统星座自主定轨中,SST(satellite to satellite tracking)可以同时提供轨道的大小、形状和星座相对方位信息,但不能确定星座的绝对定向。针对这一亏秩问题,联合圆型限制性三体模型CRTBP(circle restricted three bodyproblem)下的... 详细信息

在传统星座自主定轨中,SST(satellite to satellite tracking)可以同时提供轨道的大小、形状和星座相对方位信息,但不能确定星座的绝对定向。针对这一亏秩问题,联合圆型限制性三体模型CRTBP(circle restricted three bodyproblem)下的一种平动点周期轨道-Halo轨道飞行器,与二体问题轨道卫星组成扩展星座。利用两种力模型的特性差异,可以去除星座系统上的相关性,避免星座的整体旋转,从而确定星座的全部轨道状态参量。分析Halo轨道的力模型及性态特点,从系数矩阵的相关性角度讨论引进Halo轨道对定轨法矩阵正定性的改善作用,利用地月系L1平动点附近的Halo轨道与月球低轨卫星(LMO)的星间链路,在理想CRTBP框架下进行自主定轨仿真。初步验证了LMO-Halo星座定轨可行性,为开展附加平动点轨道的星座SST定轨提供了参考依据。

关键词：圆型限制性三体问题平动点星间跟踪SST Halo轨道低轨月球卫星

Towards Cis-Lunar Navigation: Design and Analysis of a SmallSat System with Time-Transfer from BDS

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Towards Cis-Lunar Navigation: Design and Analysis of a Small...

The Lower Cambrian Xiaoerbulake Formation in the Tarim Basin as a potential carbonate source rock

第十四届中国卫星导航年会

作者： Xiao Chen zhongkai zhang Yong Zheng zhanglei Chen Conghai Ruan Information Engineering University

The Moon, as the only natural satellite of the Earth, is a crucial destination for human space exploration and serves as a foundation for deeper space exploration. Cis-lunar space offers vast opportunities for human expansion beyond the Earth's land and ocean. The exploration, construction, and development of cis-lunar space demand enhanced cis-lunar space navigation. While GNSS navigation technology for the Earth and near-Earth space is well-established, extending it to cis-lunar space is the current stage. Small satellite technology development provides new ideas for efficient and rapid deployment of small satellite navigation constellations. To meet the cis-lunar space navigation demands, we propose a small space-based navigation system using BDS for time-transfer, based on Earth-Moon libration points orbits and small satellite platform. In this paper, we systematically study the multi-type orbital and navigation characteristics adopted, and design and analyze the architecture of the cis-lunar space small satellite navigation system using BDS timing. The proposed navigation constellation using multiple types of orbits, including DRO, NRHO, etc., is timed through BDS to compensate for the limited load of small satellites and the limited accuracy of the star clock. We analyze the observability of navigation constellations and evaluate the navigation performance of several constellation design cases using corresponding accuracy indicators. Our results verify the feasibility and preliminary performance of the proposed cis-lunar space small satellite navigation system using BDS as time-transfer, and provide a reference for BDS and GNSS to provide navigation services to cis-lunar space. We propose a new idea and method for cis-lunar space navigation that combines BDS navigation technology and small satellite platform, and which holds great promise for future space exploration.

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Energy Geoscience 2024年第2期5卷 40-52页

作者： Miaoqing Miao Zhichao Sun Zongan Xue Miao Miao Kunpeng Jiang Xuefeng zhang zhongkai Bai Xiuxiang Lyu Xingui Zhou Yongjin Gao Miao Han Youxing Yang Oil and Gas Survey CGSBeijing100083China School of Earth and Space Sciences Peking UniversityBeijing100871China Institute of Energy Peking UniversityBeijing100871China State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China School of GeoSciences China University of Petroleum(Beijing)Beijing102249China

The oil and gas exploration of the Middle and Lower Cambrian in the Tarim Basin reveals widely distributed source rocks with the Yuertusi Formation being recognized as high-quality source rocks that are distributed in a rather small *** Xiaoerbulake Formation that is right under the Yuertusi Formation has also been eyed as potential high-quality source rocks and is studied through analyses focusing on the stratigraphic development,the abundance,type,and maturity of organic matter,and the paleoproductivity of a dark-colored algae dolomite within the *** results show that the dolomite is rich in organic matter of mainly types Ⅰ and Ⅱ *** reached the high mature to over-mature stage,the dolomite was deposited in an anoxic sedimentary environment featuring a high paleoproductivity level and a high organic carbon burial efficiency,quite favorable for the development of high-quality source *** study provides material evidence to the Middle-Lower Cambrian subsalt source rock-reservoir-caprock combination model for the Tarim Basin.

关键词： Source rock Algal dolomite Yuertusi formation Xiaoerbulake formation Tarim basin

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一种亮星识别算法及其在天文定向中的应用

测绘学报 2015年第3期44卷 257-263,273页

作者：詹银虎郑勇张超李铸洋张中凯信息工程大学导航与空天目标工程学院河南郑州450001

基于全站仪对任意亮星的观测采样,提出了一种利用高度角序列和水平角速率进行联合匹配的任意亮星识别算法。通过引入天体地平坐标计算程序,算法可正确辨别行星和恒星。本文分析了任意亮星高度角和水平角速率的观测误差和计算误差,以此... 详细信息

基于全站仪对任意亮星的观测采样,提出了一种利用高度角序列和水平角速率进行联合匹配的任意亮星识别算法。通过引入天体地平坐标计算程序,算法可正确辨别行星和恒星。本文分析了任意亮星高度角和水平角速率的观测误差和计算误差,以此给出了匹配阈值条件的设定依据,并在此基础上制定了有效的匹配策略。仿真计算及实际观测试验均表明,该算法具有100%的识别成功率,远优于现有算法。将此算法应用于任意亮星天文定向,定向结果的内符合精度达到2″,外部检核精度达到1.6″。采用多颗任意亮星进行定向,可有效减弱由测站位置误差引入的定向系统误差,提高绝对定向精度。本文提出的天文定向适用于多云及雾霾天气。

关键词：天文定向恒星识别任意亮星

A thin-film temperature sensor based on a flexible electrode and substrate

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Microsystems & Nanoengineering 2021年第3期7卷 125-138页

作者： Zhaojun Liu Bian Tian Bingfei zhang Jia ngjiang Liu zhongkai zhang Song Wang Yunyun Luo Li bo Zhao Peng Shi Qijing Lin Zhuangde Jiang State Key Laboratory for Mechanical Manufacturing Systems Engineering Xi'an Jiaotong University710049 Xi'anChina

Accurate temperature measurements can efficiently solve numerous critical problems and provide key ***,a flexible micro-three-dimensional sensor,with a combination of platinum and indium oxide to form thermocouples,is designed and fabricated by a microfabrication process to achieve in situ real-time temperature *** stability and reliability of the sensor are greatly improved by optimizing the process parameters,structural design,and preparation methods.A novel micro-three-dimensional structure with better malleability is designed,which also takes advantage of the fast response of a two-dimensional thin *** as-obtained flexible temperature sensor with excellent stability and reliability is expected to greatly contribute to the development of essential components in various emerging research fields,including bio-robot and healthcare *** model of the application sensor in a mask is further proposed and designed to realize the collection of health information,reducing the number of deaths caused by the lack of timely detection and treatment of patients.

关键词： robot electrode stability

Highly sensitive flexible heat flux sensor based on a microhole array for ultralow to high temperatures

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Microsystems & Nanoengineering 2023年第5期9卷 345-356页

作者： Le Li Bian Tian zhongkai zhang Meng Shi Jiangjiang Liu Zhaojun Liu Jiaming Lei Shuimin Li Qijing Lin Libo Zhao Zhuangde Jiang School of Mechanical Engineering Xi’an Jiaotong University710049 Xi’anChina State Key Laboratory for Manufacturing Systems Engineering International Joint Laboratory for Micro/Nano Manufacturing and Measurement TechnologiesXi’an Jiaotong University(Yantai)Research Institute for Intelligent Sensing Technology and SystemXi’an Jiaotong UniversityXi’an 710049China Shandong Laboratory of Yantai Advanced Materials and Green Manufacturing Yantai 265503China

With the growing demand for thermal management of electronic devices,cooling of high-precision instruments,and biological cryopreservation,heat flux measurement of complex surfaces and at ultralow temperatures has become highly ***,current heat flux sensors(HFSs)are commonly used in high-temperature scenarios and have problems when applied in low-temperature conditions,such as low sensitivity and *** this study,we developed a flexible and highly sensitive HFS that can operate at ultralow to high temperatures,ranging from−196°C to 273°*** sensitivities of HFSs with thicknesses of 0.2 mm and 0.3 mm,which are efficiently manufactured by the screen-printing method,reach 11.21μV/(W/m2)and 13.43μV/(W/m2),*** experimental results show that there is a less than 3%resistance change from bending to ***,the HFS can measure heat flux in both exothermic and absorptive cases and can measure heat flux up to 25 kW/***,we demonstrate the application of the HFS to the measurement of minuscule heat flux,such as heat dissipation of human skin and cold *** technology is expected to be used in heat flux measurements at ultralow temperatures or on complex surfaces,which has great importance in the superconductor and cryobiology field.

关键词： high stretching superconductor